Ceiling lamp



FIG. 1 is a front view of my new design relating to a ceiling lamp, the rear view being identical;

FIG. 2 is a left side view thereof, the right side view being identical;

FIG. 3 is a bottom plan view thereof; and,

FIG. 4 is a top plan view thereof. 

The ornamental design for a ceiling lamp, substantially as shown and described. 